(1) Field of Invention
This invention relates to apparatus for ice making and is especially suited for easy installation at the factory or on site as an improvement for commercial ice cube makers.
(2) Description of Prior Art
Conventional commercial ice cube makers consume a great deal of electrical energy as the compressors process the ambient temperature tap water to near freezing temperature and distribute it over the head of the ice making section to form ice cubes. Many of the prior art attempts to speed up the process have introduced additional complex equipment which in themselves have consumed further energy rather than saving it. The present invention solves this problem by speeding up the ice making process, thus increasing its productivity and efficiency, at a savings in energy rather than consuming additional energy.
Illustrative of early ice making machines is that of Church (1894), U.S. Pat. No. 529,345. His machine had a horizontal supporting bed, with water confining sides and means for applying a freezing agent to the bottom only of the bed. Controlling the speed of the freezing and movement of the surface water were used to avoid air bubbles and to facilitate the release of the frozen ice. Freeston's apparatus of 1901, U.S. Pat. No. 672,036, illustrated another approach to ice making where the temperature of the tap water is reduced by passing it through a cooling tank first and then into a freezing or ice forming tank where the water was kept motionless during the freezing process. Liberation of air and gases from the water was accomplished by preheating the water prior to passage to the cooling tank. Surplus cool water from the freezing tank was periodically pumped back up to the cooling tank. Brine or ammonia was used as the freezing media.
Howe's apparatus of 1956, U.S. Pat. No. 2,775,100, is illustrative of ice makers wherein water which collects in the freezing tank is discharged at the end of each freezing cycle to prevent the concentration of minerals which might otherwise occur. As the water is discharged, it proceeds to a receiver where it is placed in a heat exchange relationship with the new water from the city supply which will ultimately enter the freezing tank. Bayston's 1960 apparatus, U.S. Pat. No. 2,949.752, is addressed to the making of ice cubes in great quantity by pairing freezing units back to back. The water is precooled by passing through an open topped reservoir before entering the dual freezing units where the water is frozen under conditions of continuous flow. Excess water from the freezing units is caught by the reservoir and thereby reenters the freezing cycle. Alt's ice maker of 1962, U.S. Pat. No. 3,021,686, also uses recirculation of the freezing water over the ice forming members to reduce the time of ice formation.
Cornelius's apparatus of 1972, U.S. Pat. No. 3,665,722, is addressed to controlling the degree of cooling of the liquid that takes place in coin operated cold drink dispensers. The amount of liquid dispensed is controlled by a timer. Larriva's refrigeration booster of 1973, U.S. Pat. No. 3,779,029, seeks to increase the thermal effectiveness of an ice maker by an auxiliary refrigeration unit cooling coil, plus two other coils containing refrigerants which cool the water on the way to the ice maker.
As can be seen, prior art devices to enhance icemaking have involved the recirculation of the water from reservoirs directly below the freezing units or involved auxiliary units containing refrigerants. The present invention offers savings beyond these improvements by utilizing the cooling energy from the residual ice water draining from storage bins and the cooling energy of the stored ice cubes awaiting use.
Prior art known to this inventor includes the following U.S. Patent Numbers:
______________________________________ 529,345 11/1894 Church 672,036 4/1901 Freeston 2,775,100 12/1956 Howe 2,949,752 8/1960 Bayston 3,021,686 2/1962 Alt 3,665,722 5/1972 Cornelius 3,779,029 12/1973 Larriva ______________________________________